GRAS 45BD AutoKEMAR Automotive Head and Torso Simulator

Introduction

Today’s drivers expect more than performance, they demand a quiet, refined ride and an immersive audio experience. Whether powered by a traditional combustion engine or an electric drivetrain, in-cabin acoustic quality has become a defining factor in modern automotive design.

From benchmarking and tuning premium sound systems to sound quality testing, or minimizing unwanted noise and optimizing NVH (Noise, Vibration, and Harshness) performance, achieving excellence requires precise, repeatable, and realistic acoustic measurements.

AutoKEMAR’s human-like acoustic properties allow engineers to perform accurate in-cabin measurements that closely replicate how sound behaves around a real occupant. The result is data you can trust, enabling better sound system design, more effective noise control, and a superior driving experience.

Key Features

• Widest and most flexible positioning capabilities and motion range in the market.
• Available in multiple configurations.
• User reconfigurable: One unit -> Multiple applications.
• Multiple types of microphones, ear simulators and pinnae available.
• Accurate positioning, & Precision: Ensures consistent and repeatable measurements.
• Human-Like Acoustics: Mimics human head and torso for accurate sound simulation.
• Mouth simulator option available (can be retrofitted).
• Low-noise version available (11.5 dBA).
• Easy-access cable connector panel.
• ISOFIX-compatible for secure mounting.
• Lashing Strap secure mounting system for non-ISOFIX compatible car seats.
• Rattle free operation Rattle free operation (Static, Dyno, On-road Tests).
• TEDS compatible.
• Equalization curves available: Free-field, Diffuse-field and Direction Independent.

Typical Applications and Use

Automotive in-cabin acoustics: 

• Audio system performance & tuning
• Sound Quality & Sound Design
• Infotainment and DSP testing
• Speech intelligibility and voice quality
• Hands-free communication
• In-cabin NVH
• Wind tunnel measurements

Other: 

• Vehicles Exterior Sound / Noise
• eVTOL, Trains, Airplane cabins, etc.
• Any applications that will benefit from HATS (Consumer electronics: headphones, headsets, smart speakers. Hearing aids testing)

Wide range of movement

Thanks to its ingenious seat-mount design, the GRAS 45BD AutoKEMAR offers the widest and most flexible range of motion available on the market.

This advanced fixture allows precise head and torso movement across all typical seating and driving positions, and even more extreme or unconventional setups, such as those representing very short or tall occupants, or relaxed resting positions.

By accommodating this broad range of realistic body postures, AutoKEMAR enables comprehensive and highly representative in-cabin acoustic testing, ensuring that every relevant listening position can be evaluated to take vehicle acoustics to the next level.

AutoKEMAR allows for multiple degrees of manual movement:

• Neck Rotation
• Height
• Seat Distance
• Tilt Angle Frontwards and Backwards
• Vertical Viewing Angle

User-Reconfigurable: One AutoKEMAR - Multiple applications

Built on the same proven platform as the original GRAS KEMAR, the AutoKEMAR is designed for easy reconfiguration and maximum versatility.

Thanks to its snap-fit system, users can quickly remove and replace ear simulators, microphones, and pinnae, making it simple to adapt the fixture to different test setups or measurement needs. Multiple pinna types are available to match a variety of acoustic conditions.

This flexibility allows different teams to use the same AutoKEMAR for a wide range of applications, from sound-quality benchmarking and voice-quality evaluation to telecommunications testing inside the vehicle.

Each AutoKEMAR can be upgraded or reconfigured in just minutes using readily available spare parts, ensuring that your investment stays future-proof and adaptable to evolving automotive acoustics needs.

ISOFIX Compatibility

The GRAS 45BD AutoKEMAR features a seat-mount system fully compatible with ISOFIX, allowing it to be securely fastened to a car seat for stable and repeatable in-cabin measurements. When mounted using ISOFIX, AutoKEMAR achieves maximum stability and precision, ensuring the widest possible range of movement while maintaining a firm, vibration-free position against the seat.

No ISOFIX? No Problem

For vehicles or test setups without integrated ISOFIX anchor points, standard or custom ISOFIX adapters can be used to ensure a secure installation. In addition, every AutoKEMAR includes telescopic arms and a ratchet lashing strap system, allowing the Seat Mount to be firmly secured even when ISOFIX is not available.

Mouth Simulator Option

The GRAS 45BD AutoKEMAR can be equipped with an optional mouth simulator, enabling realistic speech and voice testing inside the vehicle cabin. The mouth simulator acts as an acoustic sound source located inside the head, emitting audio signals through AutoKEMAR’s mouth opening.

When equipped with a mouth simulator, the AutoKEMAR is a comprehensive solution for in-car microphone testing, speech intelligibility measurements, and evaluation of voice-control and hands-free communication systems.

It can be ordered with a mouth simulator or upgraded later through a retrofit option.

Rattle free design

Every component of the GRAS 45BD AutoKEMAR, from the head and torso to the seat-mount assembly, is engineered for rattle-free performance.

This robust design ensures stable and noise-free operation, even in demanding test environments. As a result, AutoKEMAR is suitable not only for static in-cabin measurements, but also for tests conducted on dynamometers and even light on-road evaluations when secured with the ISOFIX mount or the Ratchet Lashing Strap system.

With its vibration-resistant construction, AutoKEMAR delivers consistent, high-fidelity acoustic data under real-world testing conditions.

Compatibility

The GRAS 45BD AutoKEMAR is available in multiple configurations, featuring various combinations of microphones, pinnae, ear simulators, and mouth simulators to meet specific testing needs.

The acoustic signals captured by AutoKEMAR’s two “ears” are output as analog voltage signals proportional to the measured sound pressure. The microphones and ear simulators require a CCP (Constant Current Power) supply, also known as IEPE, ICP, or CCLD, and AutoKEMAR is fully compatible with all these standards.

If your data acquisition (DAQ) system does not provide a CCP supply, an external CCP power module can be used. Alternatively, AutoKEMAR’s internal microphones can operate from a +48V Phantom Power supply when paired with an adapter such as the GRAS AG0003.

For setups including a mouth simulator, AutoKEMAR requires an analog signal from an external signal generator. The mouth simulator can be used in either passive mode (driven externally) or active mode (with a built-in amplifier).

Quality & Warranty

The GRAS 45BD AutoKEMAR is built from premium components sourced from the GRAS standard portfolio, all manufactured with high-quality materials and precision-engineered parts to ensure long-term stability, durability, and performance.

Every unit undergoes rigorous quality control to meet GRAS’s exacting standards for reliability and repeatability. This commitment to excellence allows us to offer a two-year warranty covering defects in materials and workmanship.

Exceptions:

• Microphones supplied with AutoKEMAR are covered by a five-year warranty.
• Cables carry a six-month warranty.